The present invention relates to apparatus and methods for user identification to deny access or service to unauthorized users and, more particularly, to apparatus and methods for speaker identification to deny access of a user to a voice dialing system for unauthorized purposes such as abusing a call forwarding service.
It is known that some voice dialing systems have a call forwarding or "follow-me" feature. Such a feature permits a person (user) having a telephone number (extension) within the voice dialing system, e.g., an employee, to forward his telephone calls, made to that number by a caller, to a remote location where he is present. In this way, a caller may reach that person seamlessly whether that person is at the original location of the number or at the remote location to which the number has been forwarded.
However, it is also known that such a call forwarding feature may be abused by an unscrupulous system user. For instance, such a person may desire to talk with another party whose telephone is external to the voice dialing system, e.g., a phone connected to a public switching telephone network (PSTN). By the user forwarding his number to the desired partys' phone using the follow-me feature of the voice dialing system, the user may then dial his own telephone number from any location which will result in his reaching the desired party at the phone where the users' number was forwarded. In this way, the user fraudulently causes the system to treat the call as if it were an system-internal call rather than an outside call to an outside party and thus cause the system to incur the total cost of the call. Also, the actual destination of the phone call (i.e., the remote location) may be masked from the system since the telephone number dialed to reach that destination is the internal number of the system user.